February 22, 2016

"What does it take for a corn plant to grow?"We ask this many times to student groups who are on "ag day" field trips or school farm tours. Often, their responses are: sunlight, dirt (we politely correct them to soil), water, fertilizer..and yes, I've even gotten the response: God. Simply, the corn plant just needs sunlight - or solar radiation and the temperature of the environment the plant is in, soil and moisture. Especially important are temperature and moisture. More technically, there could be many answers from farmers on what all they do to make their corn grow.

Soil

Healthy soil is the basis for a healthy corn crop. Through research and technology, researchers have found out how to use fertilizers to create the perfect soil composition for growing crops to raise healthy food. Corn must have adequate amounts of nitrogen (N) and phosphorus (P) for profitable production.

Profitable and environmentally sensitive corn production requires that N and P be managed in an efficient manner. (That's why farmers never just "dump" fertilizer on their crops). Also, farmers use farming production methods like "no-till", which keeps more nutrients in the soil and decreases erosion, and crop rotation which allows for legumes, like soybeans, to return N back into the soil naturally.

Moisture

In Nebraska, we are blessed with irrigation and usually consistent rainfall, which helps us cover the moisture part. Even then, new technologies with irrigation are making it even more efficient to keep the corn plant hydrated. Even then, we must rely on Mother Nature - or what the student said, God - to water our crops. The current weather situation is looking rather unique with how current El Nino weather factors could turn into a La Nina weather event, which could dry up the Midwest, according to the U.S. Grains Council's recent Global Update. This would not affect the planting season, but could affect the growing season into the next year with soil moisture levels lower going into the 2017 crop planting.

Sunlight

Along with water and nutrients, solar radiation (sunlight) is an essential input for plant growth.
Plant leaves absorb sunlight and use it as an energy source in the process of photosynthesis.
A crop's ability to collect sunlight is proportional to its leaf surface area per unit of land area occupied, or its "leaf area index (LAI)." At "full canopy" development, a crop's LAI and ability to collect available sunlight are maximized.

From full canopy through the reproductive period, any shortage of sunlight is potentially limiting to corn yield.
When stresses such as low light limit photosynthesis during ear fill, corn plants remobilize stalk carbohydrates to the ear. This may result in stalk quality issues and lodging at harvest.
The most sensitive periods of crop growth (e.g., flowering and early grain fill) are often the most susceptible to stresses such as insufficient light, water or nutrients.

If you're a farmer, we'd love feedback from your farm on:"What does it take for a corn plant to grow?"